1. Technical Field
Various embodiments generally relate to a semiconductor technology, and more particularly to a semiconductor memory apparatus and an operating method thereof.
2. Related Art
An electronic device includes a lot of electronic elements, and a computer system includes lots of electronic elements such as semiconductor based electronic elements. In computer architecture, a dynamic random access memory (DRAM) is widely used as a main memory since the DRAM has the advantage of fast data input/output speed and random access. However, the DRAM stores each bit of data in a memory cell consisting of a capacitor and a transistor, and because of capacitor leakage current, the DRAM loses stored data when power supply is cut off. By contrast, a flash memory storing data in a floating gate or a charge trap layer can retain stored data even when power supply is cut off. However, the flash memory has a slower data input/output speed than the DRAM.
Recently, the emerging next-generation memory technologies such as Phase-Change Random Access Memory (PCRAM), Resistive Random Access Memory (RRAM), Magnetic Random Access Memory (MRAM), and Ferroelectric Random Access Memory (FRAM) are expected to replace the traditional memory technologies in several areas. Some of the next-generation memory technologies are expected to replace the traditional non-volatile memory technologies because they can achieve the high-speed requirement. Particularly, the PRAM storing data in chalcogenide layers by changing their resistance values is regarded as the most promising next-generation memory.